FAILED: Patch "LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT" failed to apply to 6.12-stable tree

FAILED: Patch "LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT" failed to apply to 6.12-stable tree

[Sasha Levin]

The patch below does not apply to the 6.12-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

Thanks,
Sasha

------------------ original commit in Linus's tree ------------------

From 70b0faae3590c628a98a627a10e5d211310169d4 Mon Sep 17 00:00:00 2001
From: Tiezhu Yang <yangtiezhu@loongson.cn>
Date: Tue, 10 Feb 2026 19:31:13 +0800
Subject: [PATCH] LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT

After commit 88fd2b70120d ("LoongArch: Fix sleeping in atomic context for
PREEMPT_RT"), it should guard percpu handler under !CONFIG_PREEMPT_RT to
avoid redundant operations.

Cc: stable@vger.kernel.org
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
 arch/loongarch/kernel/unwind_prologue.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/loongarch/kernel/unwind_prologue.c b/arch/loongarch/kernel/unwind_prologue.c
index 729e775bd40dd..ee1c29686ab05 100644
--- a/arch/loongarch/kernel/unwind_prologue.c
+++ b/arch/loongarch/kernel/unwind_prologue.c
@@ -65,7 +65,7 @@ static inline bool scan_handlers(unsigned long entry_offset)
 
 static inline bool fix_exception(unsigned long pc)
 {
-#ifdef CONFIG_NUMA
+#if defined(CONFIG_NUMA) && !defined(CONFIG_PREEMPT_RT)
 	int cpu;
 
 	for_each_possible_cpu(cpu) {
-- 
2.51.0

Re: FAILED: Patch "LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT" failed to apply to 6.12-stable tree

[Huacai Chen]

Hi, Sasha,

On Sun, Mar 1, 2026 at 9:27 AM Sasha Levin <sashal@kernel.org> wrote:
>
> The patch below does not apply to the 6.12-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@vger.kernel.org>.
I'm very confused because it can be applied and already here:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/queue-6.12

Huacai

>
> Thanks,
> Sasha
>
> ------------------ original commit in Linus's tree ------------------
>
> From 70b0faae3590c628a98a627a10e5d211310169d4 Mon Sep 17 00:00:00 2001
> From: Tiezhu Yang <yangtiezhu@loongson.cn>
> Date: Tue, 10 Feb 2026 19:31:13 +0800
> Subject: [PATCH] LoongArch: Guard percpu handler under !CONFIG_PREEMPT_RT
>
> After commit 88fd2b70120d ("LoongArch: Fix sleeping in atomic context for
> PREEMPT_RT"), it should guard percpu handler under !CONFIG_PREEMPT_RT to
> avoid redundant operations.
>
> Cc: stable@vger.kernel.org
> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> ---
>  arch/loongarch/kernel/unwind_prologue.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/loongarch/kernel/unwind_prologue.c b/arch/loongarch/kernel/unwind_prologue.c
> index 729e775bd40dd..ee1c29686ab05 100644
> --- a/arch/loongarch/kernel/unwind_prologue.c
> +++ b/arch/loongarch/kernel/unwind_prologue.c
> @@ -65,7 +65,7 @@ static inline bool scan_handlers(unsigned long entry_offset)
>
>  static inline bool fix_exception(unsigned long pc)
>  {
> -#ifdef CONFIG_NUMA
> +#if defined(CONFIG_NUMA) && !defined(CONFIG_PREEMPT_RT)
>         int cpu;
>
>         for_each_possible_cpu(cpu) {
> --
> 2.51.0
>
>
>
>
>